Cleaning was a dull and tiresome task—especially when magic wasn't allowed.
Harry and Neville, both earnest and hardworking, carefully polished the dusty trophies, while George and Fred barely did any cleaning before breaking into play fights.
Seeing the twins fooling around, Leonard walked over and struck up a conversation. The main topic quickly turned to their invention—the Portable Swamp.
Later, Leonard had asked Harry about it in detail, and that was when he first heard the term "Portable Swamp."
He knew exactly what that was. Back in fifth year, George and Fred had used it to turn the castle corridors into a swamp—a permanent one, no less. That version of their prank item had already been highly advanced, a far cry from the joke toy they'd used recently that couldn't even hold down a Three-Headed Dog. It had real, undeniable strategic potential.
It was a rare kind of device capable of altering terrain. Before unlocking his talent [Plant Resilience], Leonard had even considered investing in one, so his plants could spread freely anywhere and counter any kind of enemy.
However, after [Plant Resilience] reached level 16, the Portable Swamp became somewhat redundant—though not entirely useless.
Leonard's magical plants faced one particular weakness when dealing with wizards—their mobility. Apparition was a frustratingly difficult spell to counter, but if anything could restrain it, it was this so-called joke item.
Strange, wasn't it? A prank device that could actually counter one of a wizard's most agile spells.
While Apparition was convenient and fast, it still had several restrictions.
First—and perhaps the most ridiculous rule—was that it supposedly couldn't be used during combat. Of course, that was more of a guideline than a law; few truly powerful wizards actually followed it. In battle, the exchange of spells often looked like a series of frozen frames, two wizards darting around like phantoms.
Second, the Apparition destination had to be clearly remembered and completely free of obstacles. If not, the best outcome was failure—the worst was merging with solid matter.
Third, no foreign objects could be involved in the process.
That was exactly how Dobby the house-elf had died—he'd Apparated while carrying a dagger Bellatrix had thrown. Terrible luck struck when the dagger pierced his heart mid-transfer.
A wizard trying to Apparate while covered in swamp mud risked the same kind of accident.
Fourth, hesitation was fatal. Apparition wasn't true instantaneous teleportation. Leonard, who had experienced the sensation of a Portkey, understood it well—it felt more like being sucked into a singularity and spat out somewhere else. If the caster hesitated mid-transfer, their body could splinch.
It wasn't immediately fatal, but it left them completely helpless and at the mercy of others.
And for a wizard stuck in swamp muck, the first struggle would be against the swamp's own suction. One careless moment, and splinching would be inevitable.
That was why this Portable Swamp could easily be considered the perfect tool for killing or robbing someone.
When George and Fred heard that Leonard was actually interested in their prank invention, they were ecstatic—instantly deciding he was a kindred spirit.
"Our Portable Swamp is really fun, and we've set a maximum depth—no worries about anyone sinking and drowning. It's absolutely perfect for pranks."
Fred explained excitedly. "And just imagine—solid ground turning into a swamp, confident people getting covered in sludge. It's thrilling just thinking about it, right?"
"Mm-hmm… right…" Leonard replied half-heartedly, though in his mind Fred's description was already morphing into a battle scenario against a wizard.
Deploy the Portable Swamp before the opponent uses Apparition. Once they're immobilized, unleash the magical plant for a fatal strike.
Even if they excel at defensive magic, it wouldn't matter. Leonard's magical plants came with shield-piercing attacks—no magical barrier could withstand them.
What's more, the plants moved unhindered through the mud. Combined with their Devour Magic and Magical Frenzy, plus his own Magic-Eater and Self-Destruct, Leonard could wipe out an entire wizard squad in one combo.
This tactic—where escape is impossible, fighting is pointless, and defense won't hold—delighted Leonard.
Overhearing their discussion about the Portable Swamp, Harry, who had been diligently cleaning, couldn't keep quiet. "Leonard, don't let them fool you," Harry said. "Their Portable Swamp isn't durable at all. It dried up early when we faced the Three-Headed Dog and nearly got us killed."
Fred bristled. "That's because our research lacks funding!" he protested. "Otherwise, with our progress, we'd have perfected a truly effective Portable Swamp ages ago."
"Lack of funding?" Leonard eyed the pair. "How exactly?"
"Materials are expensive. We've already blown all our pocket money just on supplies. We sometimes buy new products from Zonkos' Joke Shop, and our own joke props haven't started selling."
At this, George and Fred exchanged a glance and sighed.
Leonard stroked his chin thoughtfully. "I can help you," Leonard said. "I can take care of the funding."
"Really?" George and Fred asked, surprised and delighted.
"Of course, but I have conditions," Leonard said. "We need a detailed contract specifying how the funds will be spent and the future profits. Money isn't given away for free. If you develop and sell this product later, I want a proportional share of the profits. Additionally, if you plan to sell the patent, you must offer it to me first."
Perhaps Leonard's terms were too technical, because George and Fred looked utterly bewildered, which made Leonard shake his head.
"In short, this is a serious matter. My investment means we're partners—it's not just a loan. You'll need to compensate me with a share of future profits," Leonard explained briefly.
"No problem." Hearing it concerned future matters, George and Fred responded generously.
"So when do you plan to give us the money… I mean, the funding?" Fred asked, rubbing his hands together.
Harry, Neville, and Hermione watched the three conduct their business talk with complicated expressions.
It felt like George and Fred were scamming people with a useless prank item, yet somehow, no one could deceive Leonard.
"This is serious business. Discuss it carefully. Don't end up thinking I'm deceiving you," Leonard warned upfront.
It was essentially a preemptive warning. While Leonard wouldn't actually deceive children, some things were simply destined to become his.
Take this Portable Swamp, for instance. As a future weapon crucial for assassinating wizards who can use Apparition, Leonard would never allow it to circulate freely on the market.